Character cards explained — what is inside an AI character file

Updated 2026-09-28 · Wiki

A character card is a small, portable file that describes an AI character: how it looks, how it speaks, and how it should behave in a chat. Instead of retyping the same description into every app, you keep it in one file and load it wherever you talk to the model. This article explains what is inside a card, how to open and edit one, how compatibility varies between platforms, and the ethical lines that come with sharing other people's work.

What a character card actually is

A character card packs a persona into two things: a set of structured text fields and, usually, a picture. You import the file, the app reads the fields, and the character appears ready to chat. The point of a separate file is portability. The same card can often be loaded into a desktop client, a chat website, or a mobile app without you rewriting the character each time. For where cards sit in the wider category, see what an AI companion is.

Cards come in two common shapes. The simplest is a plain JSON file: readable text you can open in any editor. The other, and the one most people meet first, is a PNG image with the same JSON tucked into its metadata. That is why a character card often looks like an ordinary picture but behaves like a file full of instructions. Nothing is hidden or encrypted; the data is simply stored in a text chunk inside the image.

The fields inside a card

Most cards reuse the same handful of fields, though the exact names differ between implementations. Treat the list below as common ground, not as an enforced standard.

You will often also see fields for creator notes, tags, a version number, and a creator name. Those are useful metadata, but they are not guaranteed to be read by every app. Precise definitions of the shared vocabulary live in the AI companion glossary.

Why the format exists

Cards spread because people wanted three things that a single app could not give them. First, reuse: write the persona once, use it in many tools. Second, sharing: post one file and someone else can import the whole character. Third, versioning: keep a copy, edit it, and roll back if a change makes the character worse. A plain file also survives the shutdown of any one service, which is a real concern in a young category.

How to open and view a card

• If the file ends in .json, open it in any text editor. The fields are plain and readable.
• If the file is a .png, the JSON is stored in the image's metadata. A metadata reader such as ExifTool, or a short script using an image library, can print it out.
• Many apps also have a built-in card viewer that shows the fields in a form, which is the easiest option when it exists.
• If a tool shows you only the picture, it is not showing you the card. Look for an export or "view details" option.

Reading the raw fields is worth the effort once. It teaches you quickly which parts drive the character's behaviour and which parts are decorative.

How to edit a card

Editing is straightforward but easy to do badly. Keep a copy of the original before you touch anything. Change one field at a time, and keep sentences short and concrete; a wall of adjectives tends to blur rather than sharpen a character. If the app has an in-app editor, use it and re-export the card when you are done. If you edit the JSON by hand, be careful with commas and quotes, since a single broken character makes the whole file unreadable.

Compatibility between platforms

This is where expectations break. There is no single authority that governs the format, so support is uneven. Some apps read every field; others use only the name, description and first message, and silently ignore the rest. Some accept PNG cards but not JSON, or the reverse. Moving a card between apps can therefore lose detail, and a character that felt rich in one place may feel flat in another.

Practical consequences:

• Test the character after every import, and read the first few replies closely.
• Assume the example dialogue and personality may be dropped, and make sure the description still carries the character on its own.
• Some platforms, including HottyChat, document which card fields they honour, which saves trial and error.
• Where a platform ignores a field, fold the important part into the description instead.

Ethical and legal boundaries

Cards are easy to copy, which makes the ethics matter.

• Other people's cards. If someone else wrote a card, give credit and respect any note about how it may be used or edited. Do not pass it off as your own.
• Art you do not own. The avatar is often a borrowed image. Reposting it as your own work is not fine, whatever the platform allows.
• NSFW cards and age gates. Explicit cards exist in public libraries, and many platforms restrict them to adults or block them outright. Follow the rules of the service you use, and keep adult content away from minors.
• Embedded instructions. Some cards contain text designed to push a model past its safety settings. You can edit a card you import, and you should feel free to.

Content can be direct and adult without being graphic, but the line belongs at the platform, not at the file. A card cannot grant permissions the service does not offer.

Key takeaways

• A character card is a portable file that bundles a persona into text fields plus an avatar.
• Cards are usually JSON, or a PNG with the JSON stored in its metadata.
• Common fields include name, description, personality, scenario, first message and example dialogue.
• Cards exist to be reused and shared, which is exactly why they leak between platforms.
• Field support varies between apps, so re-test a character after any import or migration.
• Cards carry other people's work and intentions; credit creators, respect age limits, and edit embedded text as needed.

If you are building a character rather than reading one, the step-by-step creation guide and the prompt-writing guide cover the next stage.